Time between molting for different arachnids

Almost since I began keeping arachnids I have been keeping a log of feeding, molting and rehousing of all of my arachnids. Mostly because I have the memory of a mouse, and if I don't keep track I will have no idea who is due for what, and they would all probably starve.  I have noticed, not surprisingly, that as animals get older, the time between molts grows longer.  I thought I would look a little more closely at this to see if I could figure out how to predict the next molt for an individual. Well I haven't gotten that far yet, but I did find an interesting pattern.

In the following graph the green lines represent my four Amblypygi (Tailess whip scorpions), the black lines represent three different species of tarantula, and the red line represents a single true spider, my Tegenaria gigantean (giant European house spider).  Please note, the Y-axis is a bit arbitrary.  Day 1 was simply the first day I started the log (and I got the animals at different points in the log), and the first molt wasn't necessarily the first molt ever for the animal, they may have molted before I got them. The best fit for these lines would not be a straight line, obviously, but just for interest sake I treated them as straight lines and calculated the slope.  The Amblypygi have a slope of between 103 and 185, the tarantulas between 40 and 68, and the true spider at 29.  This means that the number of days between molts for the Amblypygi goes up much more steeply as they age then either the tarantulas or the true spider. I was a bit surprised by the difference between the Amblypygi and the tarantulas, because I thought the slope might be related to the longevity of the animal, but Amblypygi and tarantulas are similarly long lived, and and least some species of tarantulas live longer.  However, Amblypygi molt their entire lives, albeit very seldom as adults.

What is the application of this?  Nothing much that I can think of . . . for now. It would be useful to be able to predict when an animal is due to molt. Usually their behavior gives it away, not feeding, hiding, etc. But sometimes we miss these subtle cues, and a cricket loose with a molting animal can be disastrous. Knowing a range of when an animal is likely to molt could make me more careful about feeding.  Also it's just kind of interesting. Another question I would really like to answer is will stress cause them to delay molting?